With other video= parameters second monitor won't work. WIth VESA it won't work too.

This feature may work only on video cards with two or more video outputs. Two video cards in one computers are not supported now.

We know that two monitors don't work on D2500..D2700 processors, Cedar Trail platform. Image on second screen is corrupted. It's driver problem, we wait when kernel coders fix it. On all other not very old graphic chips we managed to see two monitors.

Resolution must be the same as the physical monitor resolution. Monitors here are connected to VGA and DVI video outputs. Video outputs must be specified. Possible values: VGA, DVI, HDMI, LVDS, DP, VGA2, DVI2, HDMI2, LVDS2, DP2. Usually value with number 2 means second output of this type. But sometimes driver mistakes, for example on ASRock E350M1 motherboard DVI should be specified HDMI2. It's hard to explain, easier to view log and to strain intuition. Here's part of log from terminal on ASRock E350M1:

As you may see driver sees no DVI, but two HDMI outputs. First HDMI is HDMI on motherboard. The output that driver sees as second HDMI is DVI on motherboard. So for the monitor that physically connected to DVI for this motherboard on configuration file you should specify HDMI2 instead of DVI.

Positions of displays are specified by M2_position parameter:

M2_position = right-bottom

That means that second monitor is placed to the right from first monitor and they are adjusted by bottom side. Adjustment is significant when displays resolutions differ. If monitors resolutions are the same, then values =right, =right-top and =right-bottom will give the same result.

Second monitor may work in two modes:

1. You can extend one RDP session to two monitors. Just the same as mstsc.exe does. To use second monitor in this mode no special configuration file parameters needed, only M2_display= and M2_position=. Terminal will see that second monitor should be used, that no sessions for second monitor are specified, and automatically will try to extend session to both monitors. If terminal server supports. 2008R2 supports two monitors, 2003 doesn't support.

2. Different virtual screens and connections on two monitors. Just the same as on one monitor. Screens and connections for second monitor start from:

M2_next screen

Then all the same as for one monitor. Only each virtual screen starts from M2_next screen. Next config will make menu with two items on first monitor and another menu with three items on second monitor:

Re: Two monitors

Posted: Tue Aug 01, 2017 10:31 am

by robertvg

Is it also possible in the rdp session to use the two monitors in Duplicate mode ?
Ideally to let the user choose/switch between Extend and Duplicate.
At the moment in the display settings the options for this are greyed out for the user.

Re: Two monitors

Posted: Thu Aug 03, 2017 11:44 am

by akatik

There is no official Duplicate in WTware. But usually image is duplicated automatically at all video outputs, when video drivers from (U) are used, i.e. video=...(U) in config file, and second monitor (M2_next screen) is NOT specified.